Improvement in the manufacture of illuminating-gas



UNITED STATES PATENT OFFICE.

WILLIAM YOUNG, or MAGDALEN BRIDGE, AND PETER BRASH, on 'LEIITH,

. SCOTLAND.

IMPROVEMENT IN THE MANUFACTURE OF ILLUMINATING-GAS.

Specification forming part of Letters Patent No. 107,848, dated September 27,1870.

To all whom it may concern:

Be it known that we, WILLIAM YOUNG, managerofthechemical-works,MagdalenBridge,iu thecounty of Mid-Lothian, and PETER BRASH, of Leith, in same county, Scotland, soap, candie. and oil manufacturer, subjects of the Queen of Great Britain, have invented or discovered 'new and useful Improvements in the Mannfacture of Illuminating-Gas;'and we, the said WILLIAM YOUNG and PETER BRASH, do hereby declare the nature of the said invention and in What manner the same is to be performed to be particularly described and ascertained in and by the following statement thereof-that is to say: 7 I

This invention has for its object the manufacture of illuminating-gas from certain residual products from the refining of paraffiue and such like hydrocarbon oils. In the refining of these oils they are alternately treated with acids and alkalics. For this purpose the oils are placed in agitating-vessels and strong acid added, (sulphuric in preference.) The whole is then well stirred. or mixed, so as to bring the acid and oils into contact. 011 allowing the mixed oil and acid to-stand, the acid and the impurities settle to the bottom and appear as a thick tar, which is drawn oif. The remaining oils are then well washed with water and treated with caustic soda in the same way as with the acid, which also in a similar manner removes impurities in the form of tar. The mixed refuse products (acid or alkaline tars) are at present a great nuisance to the oil-refiners, and have not, as far as we know, been applied to any useful purpose in the arts. Our invention has. for its object the application of these tars to the manufacture of illuminatinggas. Toprepare them for this purpose the acid tar is placed in a suitable vessel (by preference lined with lead) and boiled up with open steam. The condensed water from the steam combines with the acid and sinks to the bottom, and is drawn off. The alkaline tar is then run in and the whole of the tars again boiled up. In this Way any acid that may be present is neutralized and leaves the tars in a purified state floatin g on the surface of the solution of salts, alkali, and other matters. recovered by evaporation.) The purified tar can now be used for gas-making by mixing it (The alkali may be with small coal, as hereinafter described, or by running it into the retorts after the charge of coal has been introduced; but it does not do so till the tar. We prefer removing the more volatile portions of the distillate, by which it becomes perfectly safe for storage and transit. When this tar-oil is used alone for the manufacture of gasiron retorts are preferable to clay, being less porous and better conductors of heat, and the distilled tar-oil is used in preference. When the retorts. are kept at a moderate gasmaking heat and the oil delivered in a continuous stream alarge volume of highly-illuminating gas is produced. This temperature suffices to convert the oil into permanent gas, but is not sufficiently high to decarbonize the gas to any great extent. In gas-works where clay retorts are wrought at high heats the best commercial resul tswill be obtained when the gases from a ing the distillation of the charge of coal or by intimately mixing the coal and oil before chargin g. We prefer common household or splint coal for the purpose of this patent. The coal should be pulverized or in the state known as dross or slack, and the oil may be advantageously mixed in the proportion of thirty gallons per ton of coal but the proportion may be either less or more, according to the quality of gas desired. The oil, in this case may be used in its undistilled state. The oil, when used alone or with coal, gives a permanent gas, different in this respect from gas produced from a mixture of coal and shale oils. most entirely free from sulphur, so that its purification is exceedingly easy. In place of using coal as the mixing material, any substance givin g a large yield of poor gassuch as peat, sawdust, or spent bark-will answer the purpose. Either the acid or alkaline tar may be used separately, if desired; but the acid and alkali by preference are first removed from them. The acid tar maybe prepared by adding to it common salt in such quantity that the sulphuric acid may all be converted into sulphate of soda. The hydrochloric acid produced escapes dur- The oil is aling the boiling, which is conducted in the manner already described. The alkaline tar may be prepared by simply boiling it with steam in the mannerdescribed and adding common salt, allowing it to stand, when the tarry matter separates and floats on the surface. It is, however, better and more economical to mix the acid and alkaline tars and treat them together.

Having thus described the nature of our said invention and the manner of performing the same, we would have it understood that what we claim is 1. The manufacture of illuminating-gas, as herein described, from the tar or tars resultin g from the purification of paraffine and such like hydrocarbon oil.

2. The manufacture of illuminating-gas, as

herein described,.frorn the acid and alkaline tars resulting from the purification of parafiine and such like hydrocarbon oil, mixed together and treated substantially as set forth.

3. The manufacture of illuminating-gas, as herein described, from a compound of coal or other substance yielding gas of low illuminating-power and the tar or tars resulting from the purification of paraffine or such like hydrocarbon oil.

WILLIAM YOUNG. PETER BRASH.

Witnesses:

WM. LOWSAN, ALEXR. CLARK, Both of N0. 55 Constitution Street, Leith. 

